Matrix type foam wave-absorbing material based on coding metamaterial concept and preparation method of matrix type foam wave-absorbing material

Abstract

The invention provides a matrix type foam wave-absorbing material based on a coding metamaterial concept, and the matrix type foam wave-absorbing material based on the coding metamaterial concept comprises a bottom plate and units which are periodically arranged on the bottom plate. The information coding concept is introduced into metamaterial design, discrete units are arranged according to a specific coding rule, and electromagnetic waves are flexibly regulated and controlled while the inherent advantages of a foam wave-absorbing material are reserved. Besides, different wave-absorbing units are coded and combined, so that multi-band synergistic absorption can be realized, the overall density of the material can be reduced by optimizing unit distribution, the design concept breaks through a single performance optimization mode of a traditional material, and a new paradigm is provided for developing a novel wave-absorbing material with multiple functions of invisibility, bearing, sensing and the like. And the structure is simple, the preparation method is simple and convenient, modular assembly is easy, and engineering application is facilitated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electromagnetic wave absorption, in particular to a matrix type foam wave absorbing material based on the concept of coded metamaterial and a preparation method thereof. BACKGROUND

[0002] Under the background of the rapid development of modern detection technology and precision guided weapons, electromagnetic stealth technology has become a core element to ensure the survivability of military equipment. The application of wave absorbing materials greatly improves the survivability of stealth equipment (such as stealth warplanes, stealth warships, etc.) under enemy radar detection, which helps the stealth equipment to better avoid enemy reconnaissance and attack when performing tasks, and improves combat effectiveness. As a typical wave absorbing material, foam wave absorbing material belongs to a structure-function integrated wave absorbing material, which has certain load-bearing capacity and also has functions such as wave absorption, heat insulation, shock absorption, etc.

[0003] Foam wave absorbing materials are usually prepared by molding process, which can produce foam wave absorbing materials with specific porosity and pore size distribution. The molding process has good repeatability and batch production capacity, and is suitable for large-scale industrial production. The doping of one or more absorbents plays a key role in the foam wave absorbing material. Different types of absorbents have different electromagnetic loss mechanisms, which work together to achieve effective absorption and loss of electromagnetic waves.

[0004] However, the existing foam wave absorbing materials have the problems of narrow absorption bandwidth, weak wave absorption intensity, and unadjustable performance, etc. CN120005144A discloses a light-weight wide-band polyurethane foam wave absorbing material and a preparation method thereof. In the preparation of the polyurethane-based porous composite wave absorbing material, carbon-based materials and magnetic materials are added, which work together to effectively improve the wave absorbing performance of the material. However, such foam wave absorbing materials are all uniform or non-uniform plate structures, which can only absorb electromagnetic waves at fixed frequencies or frequency bands after being prepared and formed, and have limited frequency band adjustment capability and cannot be freely assembled.

[0005] In summary, there is an urgent need for a new technical solution to solve the problems existing in the prior art. SUMMARY

[0006] In view of the defects and deficiencies in the prior art, the present application provides a matrix type foam wave absorbing material based on the concept of coded metamaterial and a preparation method thereof. The present application has a simple structure and a simple preparation method, which retains the inherent advantages of foam wave absorbing materials while realizing flexible regulation of electromagnetic waves. It can realize multi-band collaborative absorption and also reduce the overall density of the material by optimizing the distribution of units, providing a new paradigm for developing new wave absorbing materials with multiple functions such as stealth, load-bearing, sensing, etc. Moreover, the present application is easy to modularize and assemble, which is conducive to engineering application.

[0007] It is an object of the present application to provide a matrix type foam wave absorbing material based on the concept of coded metamaterial, which comprises a base plate and units arranged periodically on the base plate. The units are composed of periodically arranged first foam wave absorbing material and second foam wave absorbing material.

[0008] Further, the first foam wave absorbing material and the second foam wave absorbing material comprise an absorbent, a foaming raw material and a foaming agent.

[0009] Further, the first foam wave absorbing material and the second foam wave absorbing material have different absorbents.

[0010] Further, the content of the absorbent is 0-80 wt% Further, the absorbent is selected from one or more of resistive loss absorbent, dielectric loss absorbent, magnetic loss absorbent.

[0011] Further, the foaming raw material is selected from one or more of polyether polyol, polyisocyanate, polystyrene particles, aromatic dianhydride and aromatic diamine, polyvinyl pyrrolidone.

[0012] Further, the foaming agent is selected from one or more of physical foaming agent, chemical foaming agent, surfactant foaming agent.

[0013] Further, in the first foam wave absorbing material, the absorbent is carbon fiber; the foaming raw material is polyether polyol and isocyanate; In the second foam wave absorbing material, the absorbent is polycrystalline iron fiber; the foaming raw material is polyether polyol and isocyanate.

[0014] It is another object of the present application to provide a preparation method of the matrix type foam wave absorbing material based on the concept of coded metamaterial, which comprises the following steps: S1, different absorbents are respectively blended with foaming raw material and foaming agent, stirred uniformly, then poured into a forming mold of a foam plate, and after sufficient foaming and solidification, the first plate foam wave absorbing material and the second plate foam wave absorbing material are obtained after cooling; S2, the first plate foam wave absorbing material and the second plate foam wave absorbing material are cut to obtain the first foam wave absorbing material and the second foam wave absorbing material; S3, the first foam wave absorbing material and the second foam wave absorbing material are arranged periodically to obtain units, and then the units are arranged periodically and pasted on the base plate with a high molecular material, and the matrix type foam wave absorbing material is obtained after solidification.

[0015] Further, in step S1, the mass ratio of the absorbent, the foaming raw material liquid, and the foaming agent is (1-4):(4-10):(1-2).

[0016] Further, in step S3, the arrangement interval of the first and second foam wave-absorbing materials is 5-20 mm, the size is 15-30 mm, and the unit period is 20-150 mm.

[0017] Further, in step S1, the solidification temperature is 40-80℃.

[0018] Further, in step S3, the solidification temperature is 120-150℃, and the solidification time is 1.5-3.0 h.

[0019] Further, in step S3, the high polymer material is selected from one or more of thermosetting epoxy resin and phenolic resin.

[0020] Further, the matrix-type foam wave-absorbing material exhibits a multi-absorption peak characteristic in the X-band (8.2 GHz-12.4 GHz), and the maximum peak reflection loss can reach -36.87 dB.

[0021] The present application has the following beneficial effects: The present application provides a matrix-type foam wave-absorbing material based on the concept of coded metamaterials, wherein the matrix-type foam wave-absorbing material based on the concept of coded metamaterials comprises a bottom plate and units arranged periodically on the bottom plate. In design, the present application introduces the concept of information coding into the field of metamaterials, and arranges discrete units through specific coding rules. This design not only retains the inherent advantages of foam wave-absorbing materials, but also realizes flexible regulation of electromagnetic waves. Further, the present application can achieve the effect of multi-band collaborative absorption by coding and combining different absorbing units, and can reduce the overall density of the material by optimizing the distribution of units. This design concept breaks the mode of single performance optimization of traditional materials, and provides a new paradigm for developing new wave-absorbing materials with multiple functions such as stealth, bearing, and sensing. In addition, the material also has the characteristics of simple structure, simple preparation method, and easy modular assembly, which has significant potential in engineering application. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 A unit structure front view of the matrix-type foam wave-absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0023] Figure 2 A unit structure side view of the matrix-type foam wave-absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0024] Figure 3 A perspective view of a unit structure of the matrix type foam wave-absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0025] Figure 4 A perspective view of the matrix type foam wave-absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0026] Figure 5 A reflection loss curve of the matrix type foam wave-absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0027] Figure 6 A reflection loss curve of the matrix type foam wave-absorbing material based on the concept of coded metamaterials prepared in Example 2 is shown. DETAILED DESCRIPTION

[0028] In order to more clearly illustrate the technical solutions of the present application, the following examples are listed. The raw materials, reactions and post-treatment means appearing in the examples are all common raw materials on the market and technical means well known to those skilled in the art, unless otherwise stated.

[0029] The words "preferred", "preferably", "more preferred", etc. in the present application refer to the embodiments of the present application which can provide certain beneficial effects in certain cases. However, other embodiments can also be preferred in the same or other cases. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not usable, nor is it intended to exclude other embodiments from the scope of the present application.

[0030] It should be understood that, except in any operating examples, or where otherwise indicated, expressions of amount or all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present application.

[0031] In the embodiments of the present application, the following raw materials will be used: Polyether polyol, brand PO-300, purchased from Guangzhou Xingsheng Trading Co., Ltd.; isocyanate, brand MDI, purchased from Hubei Wanxing Biological Technology Co., Ltd.

[0032] Carbon fiber, brand 12K, purchased from Shanghai Lisuo Composite Material Technology Co., Ltd.; polycrystalline iron fiber, brand 2601019, purchased from Fosamn Technology (Beijing) Co., Ltd.

[0033] Physical foaming agent, brand MS205D, purchased from Shijiazhuang Ruotuo Chemical Technology Co., Ltd.

[0034] Thermosetting epoxy resin: E51, purchased from Langfang Xingling Mingyuan Anticorrosion Material Co., Ltd.

[0035] The water in the embodiments of the present application, unless otherwise specified, refers to deionized water.

[0036] Example 1 A matrix type foam wave-absorbing material based on the concept of coded metamaterial, wherein the matrix type foam wave-absorbing material based on the concept of coded metamaterial comprises a bottom plate and units arranged periodically on the bottom plate.

[0037] The preparation method of the matrix type foam wave-absorbing material based on the concept of coded metamaterial comprises the following steps: S1, carbon fibers, polyether polyol, isocyanate, and physical foaming agent are blended in a mass ratio of 2:5:5:1, stirred uniformly, poured into a forming mold of a foam whole plate with a size of 400*400 mm, reacted for 0.5 h, allowed to foam, heated at 60℃ for 2 h until the foam is cured, and cooled to obtain a first whole plate foam wave-absorbing material with a thickness of 10 mm; S2, polycrystalline iron fibers, polyether polyol, isocyanate, and physical foaming agent are blended in a mass ratio of 3:5:5:2, stirred uniformly, poured into a forming mold of a foam whole plate with a size of 400*400 mm, reacted for 0.5 h, allowed to foam, heated at 60℃ for 2 h until the foam is cured, and cooled to obtain a second whole plate foam wave-absorbing material with a thickness of 8 mm; S3, the first whole plate foam wave-absorbing material and the second whole plate foam wave-absorbing material are cut into foam small plates with a size of 20*20 mm using a constant temperature heating blade at 150℃ to obtain a first foam wave-absorbing material and a second foam wave-absorbing material; S4, the first foam wave-absorbing material and the second foam wave-absorbing material are respectively marked as 0 and 1, arranged alternately into a 3*3 matrix in the order of the first row being "010", the second row being "101", and the third row being "010" with a spacing of 6 mm, to obtain a unit with a size of 72*72 mm, then nine units are periodically arranged according to 3*3 with a spacing of 6 mm, and pasted on a copper metal bottom plate with a size of 234*234 mm and a thickness of 2 mm using thermosetting epoxy resin, transferred to a digital constant temperature drying box, and cured at 120℃ for 2 h to obtain a matrix type foam wave-absorbing material.

[0038] Figure 1 A unit structure front view of the matrix type foam wave-absorbing material based on the concept of coded metamaterial prepared in Example 1 is shown.

[0039] Figure 2A side view of a unit structure of a matrix type foam wave absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0040] Figure 3 A perspective view of a unit structure of a matrix type foam wave absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0041] Figure 4 A perspective view of a matrix type foam wave absorbing material based on the concept of coded metamaterials prepared in Example 1 is shown.

[0042] Example 2 A matrix type foam wave absorbing material based on the concept of coded metamaterials, wherein the matrix type foam wave absorbing material based on the concept of coded metamaterials comprises a bottom plate and units arranged periodically on the bottom plate.

[0043] A preparation method of the matrix type foam wave absorbing material based on the concept of coded metamaterials, comprising the following steps: S1, carbon fibers, polyether polyol, isocyanate, and physical foaming agent are blended in a mass ratio of 3:6:6:2, stirred uniformly, poured into a forming mold of a foam whole plate with a size of 400*400 mm, reacted for 1 h, allowed to foam, heated at 80℃ for 1.5 h until the foam is cured, and cooled to obtain a first whole plate foam wave absorbing material with a thickness of 10 mm; S2, polycrystalline iron fibers, polyether polyol, isocyanate, and physical foaming agent are blended in a mass ratio of 2:5:5:2, stirred uniformly, poured into a forming mold of a foam whole plate with a size of 400*400 mm, reacted for 1 h, allowed to foam, heated at 80℃ for 1.5 h until the foam is cured, and cooled to obtain a second whole plate foam wave absorbing material with a thickness of 8 mm; S3, the first whole plate foam wave absorbing material and the second whole plate foam wave absorbing material are cut into foam small plates with a size of 20*20 mm using a constant temperature heating blade at 170℃, to obtain a first foam wave absorbing material and a second foam wave absorbing material; S4, the first foam wave absorbing material and the second foam wave absorbing material are respectively marked as 0 and 1, arranged alternately into a 2*2 matrix in the order of the first row "01" and the second row "10" with a spacing of 6 mm, to obtain a unit with a size of 46*46 mm, then nine units are periodically arranged according to 3*3 with a spacing of 5 mm, and pasted on a copper metal bottom plate with a size of 153*153 mm and a thickness of 2 mm using a thermosetting epoxy resin, transferred to a digital constant temperature drying box, and cured at 120℃ for 2 h to obtain a matrix type foam wave absorbing material.

[0044] Comparative Example A comparative example is set based on the example, and the difference from Example 1 is that: The first whole plate of foam wave-absorbing material prepared in step S1 is cut into a size of 234*234 mm, and without steps S2, S3 and S4, the first whole plate of foam wave-absorbing material with a size of 234*234 mm is pasted on a copper metal bottom plate with a thickness of 2 mm by using a thermosetting epoxy resin, and is transferred to a digital constant temperature drying box, and after being cured at 120℃ for 2 h, a foam wave-absorbing material is obtained.

[0045] Test Example The matrix type foam wave-absorbing materials prepared in Examples 1-2 and the foam wave-absorbing material prepared in the comparative example are subjected to performance testing.

[0046] Test Method: A test system composed of an arc method and an Agilent N5230A vector network analyzer is used to measure and collect the echo loss parameters in a microwave darkroom, and a change curve of the material reflection loss is drawn by conversion processing according to a reflection loss calculation formula dB=10*log (reflectivity).

[0047] The test results are shown in Table 1.

[0048] Table 1 Performance test results Figure 5 A reflection loss curve diagram of the matrix type foam wave-absorbing material based on the concept of coded metamaterial prepared in Example 1 is shown.

[0049] Figure 6 A reflection loss curve diagram of the matrix type foam wave-absorbing material based on the concept of coded metamaterial prepared in Example 2 is shown.

[0050] As can be seen from the figures, the performance data of the matrix type foam wave-absorbing materials based on the concept of coded metamaterial prepared in Examples 1 and 2 are shown in Table 1. According to Table 1, it can be seen that under the condition that the total sample thickness is the same, the effective absorption bandwidth, minimum reflection loss and other performance indicators of the matrix type foam wave-absorbing materials based on the concept of coded metamaterial prepared in Examples 1 and 2 are all better than those of the comparative example, so it can be seen that the matrix type foam wave-absorbing material prepared in the present application optimizes the structure of the traditional foam wave-absorbing material, and can achieve the effect of multi-band collaborative absorption.

[0051] It will be obvious to a person skilled in the art that the application is not limited to the details of the above-described exemplary embodiments, but that the application can be implemented in other embodiments without departing from the spirit or essential characteristics of the application. The embodiments should, therefore, be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

[0052] Furthermore, it should be understood that although the description is made on embodiments, not every embodiment contains only one independent technical solution, and the description is made in this way only for the sake of clarity, and a person skilled in the art should consider the description as a whole, and the technical solutions in each embodiment can also be combined appropriately to form other embodiments that can be understood by a person skilled in the art.

Claims

1. A matrix type foam wave-absorbing material based on the concept of coded metamaterials, characterized by, The matrix type foam wave-absorbing material based on the coding metamaterial concept comprises a bottom plate and units periodically arranged on the bottom plate. The units are composed of periodically arranged first foam wave-absorbing material and second foam wave-absorbing material.

2. The matrix-type foam wave-absorbing material based on the coded metamaterial concept according to claim 1, characterized in that, The first foam wave-absorbing material and the second foam wave-absorbing material comprise an absorbent, a foaming raw material and a foaming agent.

3. The matrix-type foam wave-absorbing material based on the coded metamaterial concept according to claim 2, characterized in that, The first foam wave-absorbing material and the second foam wave-absorbing material have different absorbents.

4. The matrix-type foam wave-absorbing material based on the coded metamaterial concept according to claim 2, characterized in that, The absorbent is selected from one or more of resistive loss absorbent, dielectric loss absorbent and magnetic loss absorbent.

5. The matrix-type foam wave-absorbing material based on the coding metamaterial concept according to claim 2, characterized in that, The foaming raw material is selected from one or more of polyether polyol, polyisocyanate, polystyrene particles, aromatic dianhydride and aromatic diamine, and polyvinylpyrrolidone.

6. The matrix-type foam wave-absorbing material based on the coded metamaterial concept according to claim 2, characterized in that, The foaming agent is selected from one or more of physical foaming agent, chemical foaming agent and surfactant foaming agent.

7. The method of claim 1-6 for preparing a matrix-type foam wave-absorbing material based on the concept of coding metamaterials, characterized in that, The preparation method of the matrix type foam wave-absorbing material based on the coding metamaterial concept comprises the following steps: S1, different absorbents are respectively blended with foaming raw material and foaming agent, stirred uniformly, then poured into a forming mold of a foam whole plate, and after sufficient foaming and solidification, the first whole plate foam wave-absorbing material and the second whole plate foam wave-absorbing material are obtained after cooling; S2, the first whole plate foam wave-absorbing material and the second whole plate foam wave-absorbing material are cut to obtain the first foam wave-absorbing material and the second foam wave-absorbing material; S3, the first foam wave-absorbing material and the second foam wave-absorbing material are periodically arranged to obtain units, and then the units are periodically arranged and pasted on the bottom plate with a high molecular material, and the matrix type foam wave-absorbing material is obtained after solidification.

8. The method for preparing matrix-type foam absorbing material based on the concept of coded metamaterials according to claim 7, characterized in that, In step S1, the mass ratio of the absorbent, the foaming raw material liquid and the foaming agent is (1-4):(4-10):(1-2).

9. The method for preparing matrix-type foam absorbing material based on the concept of coded metamaterials according to claim 7, characterized in that, In step S1, the solidification temperature is 40-80℃.

10. The method for preparing matrix-type foam absorbing material based on the concept of coded metamaterials according to claim 7, characterized in that, In step S3, the solidification temperature is 120-150℃.

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